these are pricey but they beat digging wire out of yourself and your clothes. they come in different grits and sizes and in roloc versions. you can probably find them cheaper I just posted the first link that came up.
A wire wheel on a grinder knocks a lot out pretty fast. A flap disc for cleanup. As I sit and think about it, that's the only way I've tried that works really well. I want to try the sand blasting with a pressure washer, but I don't think my pressure washer was up to the task. I forget why, but I left that thought alone. I think it was not enough GPM. Then there's the needle scaler.
After rust cleanup, maybe get the steel clean and dry, prime and paint. I don't do anything that important, so priming is never on my list. Just throw some paint on it, and on to the next. Clean and touch up later on.
If your parts are small enough, make an immersion tank filled with Evapo-Rust. It is safe for handling bare handed and can be used and reused many times. Blow dry and paint immediately if you are on the gulf coast. Rust bloom can happen there in 15 minutes, I have seen it happen that quickly.
It does take a minimum of 24 hours in the tank with Evapo-rust to remove the rust from most surfaces. The good thing is you can leave it for days and wont hurt a thing.